1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PROCESSOR_H
3 #define _ASM_X86_PROCESSOR_H
4 
5 #include <asm/processor-flags.h>
6 
7 /* Forward declaration, a strange C thing */
8 struct task_struct;
9 struct mm_struct;
10 struct io_bitmap;
11 struct vm86;
12 
13 #include <asm/math_emu.h>
14 #include <asm/segment.h>
15 #include <asm/types.h>
16 #include <uapi/asm/sigcontext.h>
17 #include <asm/current.h>
18 #include <asm/cpufeatures.h>
19 #include <asm/cpuid.h>
20 #include <asm/page.h>
21 #include <asm/pgtable_types.h>
22 #include <asm/percpu.h>
23 #include <asm/desc_defs.h>
24 #include <asm/nops.h>
25 #include <asm/special_insns.h>
26 #include <asm/fpu/types.h>
27 #include <asm/unwind_hints.h>
28 #include <asm/vmxfeatures.h>
29 #include <asm/vdso/processor.h>
30 #include <asm/shstk.h>
31 
32 #include <linux/personality.h>
33 #include <linux/cache.h>
34 #include <linux/threads.h>
35 #include <linux/math64.h>
36 #include <linux/err.h>
37 #include <linux/irqflags.h>
38 #include <linux/mem_encrypt.h>
39 
40 /*
41  * We handle most unaligned accesses in hardware.  On the other hand
42  * unaligned DMA can be quite expensive on some Nehalem processors.
43  *
44  * Based on this we disable the IP header alignment in network drivers.
45  */
46 #define NET_IP_ALIGN	0
47 
48 #define HBP_NUM 4
49 
50 /*
51  * These alignment constraints are for performance in the vSMP case,
52  * but in the task_struct case we must also meet hardware imposed
53  * alignment requirements of the FPU state:
54  */
55 #ifdef CONFIG_X86_VSMP
56 # define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
57 # define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
58 #else
59 # define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
60 # define ARCH_MIN_MMSTRUCT_ALIGN	0
61 #endif
62 
63 extern u16 __read_mostly tlb_lli_4k;
64 extern u16 __read_mostly tlb_lli_2m;
65 extern u16 __read_mostly tlb_lli_4m;
66 extern u16 __read_mostly tlb_lld_4k;
67 extern u16 __read_mostly tlb_lld_2m;
68 extern u16 __read_mostly tlb_lld_4m;
69 extern u16 __read_mostly tlb_lld_1g;
70 
71 /*
72  * CPU type and hardware bug flags. Kept separately for each CPU.
73  */
74 
75 struct cpuinfo_topology {
76 	// Real APIC ID read from the local APIC
77 	u32			apicid;
78 	// The initial APIC ID provided by CPUID
79 	u32			initial_apicid;
80 
81 	// Physical package ID
82 	u32			pkg_id;
83 
84 	// Physical die ID on AMD, Relative on Intel
85 	u32			die_id;
86 
87 	// Compute unit ID - AMD specific
88 	u32			cu_id;
89 
90 	// Core ID relative to the package
91 	u32			core_id;
92 
93 	// Logical ID mappings
94 	u32			logical_pkg_id;
95 	u32			logical_die_id;
96 	u32			logical_core_id;
97 
98 	// AMD Node ID and Nodes per Package info
99 	u32			amd_node_id;
100 
101 	// Cache level topology IDs
102 	u32			llc_id;
103 	u32			l2c_id;
104 
105 	// Hardware defined CPU-type
106 	union {
107 		u32		cpu_type;
108 		struct {
109 			// CPUID.1A.EAX[23-0]
110 			u32	intel_native_model_id	:24;
111 			// CPUID.1A.EAX[31-24]
112 			u32	intel_type		:8;
113 		};
114 		struct {
115 			// CPUID 0x80000026.EBX
116 			u32	amd_num_processors	:16,
117 				amd_power_eff_ranking	:8,
118 				amd_native_model_id	:4,
119 				amd_type		:4;
120 		};
121 	};
122 };
123 
124 struct cpuinfo_x86 {
125 	union {
126 		/*
127 		 * The particular ordering (low-to-high) of (vendor,
128 		 * family, model) is done in case range of models, like
129 		 * it is usually done on AMD, need to be compared.
130 		 */
131 		struct {
132 			__u8	x86_model;
133 			/* CPU family */
134 			__u8	x86;
135 			/* CPU vendor */
136 			__u8	x86_vendor;
137 			__u8	x86_reserved;
138 		};
139 		/* combined vendor, family, model */
140 		__u32		x86_vfm;
141 	};
142 	__u8			x86_stepping;
143 #ifdef CONFIG_X86_64
144 	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
145 	int			x86_tlbsize;
146 #endif
147 #ifdef CONFIG_X86_VMX_FEATURE_NAMES
148 	__u32			vmx_capability[NVMXINTS];
149 #endif
150 	__u8			x86_virt_bits;
151 	__u8			x86_phys_bits;
152 	/* Max extended CPUID function supported: */
153 	__u32			extended_cpuid_level;
154 	/* Maximum supported CPUID level, -1=no CPUID: */
155 	int			cpuid_level;
156 	/*
157 	 * Align to size of unsigned long because the x86_capability array
158 	 * is passed to bitops which require the alignment. Use unnamed
159 	 * union to enforce the array is aligned to size of unsigned long.
160 	 */
161 	union {
162 		__u32		x86_capability[NCAPINTS + NBUGINTS];
163 		unsigned long	x86_capability_alignment;
164 	};
165 	char			x86_vendor_id[16];
166 	char			x86_model_id[64];
167 	struct cpuinfo_topology	topo;
168 	/* in KB - valid for CPUS which support this call: */
169 	unsigned int		x86_cache_size;
170 	int			x86_cache_alignment;	/* In bytes */
171 	/* Cache QoS architectural values, valid only on the BSP: */
172 	int			x86_cache_max_rmid;	/* max index */
173 	int			x86_cache_occ_scale;	/* scale to bytes */
174 	int			x86_cache_mbm_width_offset;
175 	int			x86_power;
176 	unsigned long		loops_per_jiffy;
177 	/* protected processor identification number */
178 	u64			ppin;
179 	u16			x86_clflush_size;
180 	/* number of cores as seen by the OS: */
181 	u16			booted_cores;
182 	/* Index into per_cpu list: */
183 	u16			cpu_index;
184 	/*  Is SMT active on this core? */
185 	bool			smt_active;
186 	u32			microcode;
187 	/* Address space bits used by the cache internally */
188 	u8			x86_cache_bits;
189 	unsigned		initialized : 1;
190 } __randomize_layout;
191 
192 #define X86_VENDOR_INTEL	0
193 #define X86_VENDOR_CYRIX	1
194 #define X86_VENDOR_AMD		2
195 #define X86_VENDOR_UMC		3
196 #define X86_VENDOR_CENTAUR	5
197 #define X86_VENDOR_TRANSMETA	7
198 #define X86_VENDOR_NSC		8
199 #define X86_VENDOR_HYGON	9
200 #define X86_VENDOR_ZHAOXIN	10
201 #define X86_VENDOR_VORTEX	11
202 #define X86_VENDOR_NUM		12
203 
204 #define X86_VENDOR_UNKNOWN	0xff
205 
206 /*
207  * capabilities of CPUs
208  */
209 extern struct cpuinfo_x86	boot_cpu_data;
210 extern struct cpuinfo_x86	new_cpu_data;
211 
212 extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
213 extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
214 
215 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
216 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
217 
218 extern const struct seq_operations cpuinfo_op;
219 
220 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
221 
222 extern void cpu_detect(struct cpuinfo_x86 *c);
223 
l1tf_pfn_limit(void)224 static inline unsigned long long l1tf_pfn_limit(void)
225 {
226 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
227 }
228 
229 void init_cpu_devs(void);
230 void get_cpu_vendor(struct cpuinfo_x86 *c);
231 extern void early_cpu_init(void);
232 extern void identify_secondary_cpu(unsigned int cpu);
233 extern void print_cpu_info(struct cpuinfo_x86 *);
234 void print_cpu_msr(struct cpuinfo_x86 *);
235 
236 /*
237  * Friendlier CR3 helpers.
238  */
read_cr3_pa(void)239 static inline unsigned long read_cr3_pa(void)
240 {
241 	return __read_cr3() & CR3_ADDR_MASK;
242 }
243 
native_read_cr3_pa(void)244 static inline unsigned long native_read_cr3_pa(void)
245 {
246 	return __native_read_cr3() & CR3_ADDR_MASK;
247 }
248 
load_cr3(pgd_t * pgdir)249 static inline void load_cr3(pgd_t *pgdir)
250 {
251 	write_cr3(__sme_pa(pgdir));
252 }
253 
254 /*
255  * Note that while the legacy 'TSS' name comes from 'Task State Segment',
256  * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
257  * unrelated to the task-switch mechanism:
258  */
259 #ifdef CONFIG_X86_32
260 /* This is the TSS defined by the hardware. */
261 struct x86_hw_tss {
262 	unsigned short		back_link, __blh;
263 	unsigned long		sp0;
264 	unsigned short		ss0, __ss0h;
265 	unsigned long		sp1;
266 
267 	/*
268 	 * We don't use ring 1, so ss1 is a convenient scratch space in
269 	 * the same cacheline as sp0.  We use ss1 to cache the value in
270 	 * MSR_IA32_SYSENTER_CS.  When we context switch
271 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
272 	 * written matches ss1, and, if it's not, then we wrmsr the new
273 	 * value and update ss1.
274 	 *
275 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
276 	 * that we set it to zero in vm86 tasks to avoid corrupting the
277 	 * stack if we were to go through the sysenter path from vm86
278 	 * mode.
279 	 */
280 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
281 
282 	unsigned short		__ss1h;
283 	unsigned long		sp2;
284 	unsigned short		ss2, __ss2h;
285 	unsigned long		__cr3;
286 	unsigned long		ip;
287 	unsigned long		flags;
288 	unsigned long		ax;
289 	unsigned long		cx;
290 	unsigned long		dx;
291 	unsigned long		bx;
292 	unsigned long		sp;
293 	unsigned long		bp;
294 	unsigned long		si;
295 	unsigned long		di;
296 	unsigned short		es, __esh;
297 	unsigned short		cs, __csh;
298 	unsigned short		ss, __ssh;
299 	unsigned short		ds, __dsh;
300 	unsigned short		fs, __fsh;
301 	unsigned short		gs, __gsh;
302 	unsigned short		ldt, __ldth;
303 	unsigned short		trace;
304 	unsigned short		io_bitmap_base;
305 
306 } __attribute__((packed));
307 #else
308 struct x86_hw_tss {
309 	u32			reserved1;
310 	u64			sp0;
311 	u64			sp1;
312 
313 	/*
314 	 * Since Linux does not use ring 2, the 'sp2' slot is unused by
315 	 * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
316 	 * the user RSP value.
317 	 */
318 	u64			sp2;
319 
320 	u64			reserved2;
321 	u64			ist[7];
322 	u32			reserved3;
323 	u32			reserved4;
324 	u16			reserved5;
325 	u16			io_bitmap_base;
326 
327 } __attribute__((packed));
328 #endif
329 
330 /*
331  * IO-bitmap sizes:
332  */
333 #define IO_BITMAP_BITS			65536
334 #define IO_BITMAP_BYTES			(IO_BITMAP_BITS / BITS_PER_BYTE)
335 #define IO_BITMAP_LONGS			(IO_BITMAP_BYTES / sizeof(long))
336 
337 #define IO_BITMAP_OFFSET_VALID_MAP				\
338 	(offsetof(struct tss_struct, io_bitmap.bitmap) -	\
339 	 offsetof(struct tss_struct, x86_tss))
340 
341 #define IO_BITMAP_OFFSET_VALID_ALL				\
342 	(offsetof(struct tss_struct, io_bitmap.mapall) -	\
343 	 offsetof(struct tss_struct, x86_tss))
344 
345 #ifdef CONFIG_X86_IOPL_IOPERM
346 /*
347  * sizeof(unsigned long) coming from an extra "long" at the end of the
348  * iobitmap. The limit is inclusive, i.e. the last valid byte.
349  */
350 # define __KERNEL_TSS_LIMIT	\
351 	(IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
352 	 sizeof(unsigned long) - 1)
353 #else
354 # define __KERNEL_TSS_LIMIT	\
355 	(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
356 #endif
357 
358 /* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
359 #define IO_BITMAP_OFFSET_INVALID	(__KERNEL_TSS_LIMIT + 1)
360 
361 struct entry_stack {
362 	char	stack[PAGE_SIZE];
363 };
364 
365 struct entry_stack_page {
366 	struct entry_stack stack;
367 } __aligned(PAGE_SIZE);
368 
369 /*
370  * All IO bitmap related data stored in the TSS:
371  */
372 struct x86_io_bitmap {
373 	/* The sequence number of the last active bitmap. */
374 	u64			prev_sequence;
375 
376 	/*
377 	 * Store the dirty size of the last io bitmap offender. The next
378 	 * one will have to do the cleanup as the switch out to a non io
379 	 * bitmap user will just set x86_tss.io_bitmap_base to a value
380 	 * outside of the TSS limit. So for sane tasks there is no need to
381 	 * actually touch the io_bitmap at all.
382 	 */
383 	unsigned int		prev_max;
384 
385 	/*
386 	 * The extra 1 is there because the CPU will access an
387 	 * additional byte beyond the end of the IO permission
388 	 * bitmap. The extra byte must be all 1 bits, and must
389 	 * be within the limit.
390 	 */
391 	unsigned long		bitmap[IO_BITMAP_LONGS + 1];
392 
393 	/*
394 	 * Special I/O bitmap to emulate IOPL(3). All bytes zero,
395 	 * except the additional byte at the end.
396 	 */
397 	unsigned long		mapall[IO_BITMAP_LONGS + 1];
398 };
399 
400 struct tss_struct {
401 	/*
402 	 * The fixed hardware portion.  This must not cross a page boundary
403 	 * at risk of violating the SDM's advice and potentially triggering
404 	 * errata.
405 	 */
406 	struct x86_hw_tss	x86_tss;
407 
408 	struct x86_io_bitmap	io_bitmap;
409 } __aligned(PAGE_SIZE);
410 
411 DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
412 
413 /* Per CPU interrupt stacks */
414 struct irq_stack {
415 	char		stack[IRQ_STACK_SIZE];
416 } __aligned(IRQ_STACK_SIZE);
417 
418 DECLARE_PER_CPU_CACHE_HOT(struct irq_stack *, hardirq_stack_ptr);
419 #ifdef CONFIG_X86_64
420 DECLARE_PER_CPU_CACHE_HOT(bool, hardirq_stack_inuse);
421 #else
422 DECLARE_PER_CPU_CACHE_HOT(struct irq_stack *, softirq_stack_ptr);
423 #endif
424 
425 DECLARE_PER_CPU_CACHE_HOT(unsigned long, cpu_current_top_of_stack);
426 /* const-qualified alias provided by the linker. */
427 DECLARE_PER_CPU_CACHE_HOT(const unsigned long __percpu_seg_override,
428 			  const_cpu_current_top_of_stack);
429 
430 #ifdef CONFIG_X86_64
cpu_kernelmode_gs_base(int cpu)431 static inline unsigned long cpu_kernelmode_gs_base(int cpu)
432 {
433 #ifdef CONFIG_SMP
434 	return per_cpu_offset(cpu);
435 #else
436 	return 0;
437 #endif
438 }
439 
440 extern asmlinkage void entry_SYSCALL32_ignore(void);
441 
442 /* Save actual FS/GS selectors and bases to current->thread */
443 void current_save_fsgs(void);
444 #endif	/* X86_64 */
445 
446 struct perf_event;
447 
448 struct thread_struct {
449 	/* Cached TLS descriptors: */
450 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
451 #ifdef CONFIG_X86_32
452 	unsigned long		sp0;
453 #endif
454 	unsigned long		sp;
455 #ifdef CONFIG_X86_32
456 	unsigned long		sysenter_cs;
457 #else
458 	unsigned short		es;
459 	unsigned short		ds;
460 	unsigned short		fsindex;
461 	unsigned short		gsindex;
462 #endif
463 
464 #ifdef CONFIG_X86_64
465 	unsigned long		fsbase;
466 	unsigned long		gsbase;
467 #else
468 	/*
469 	 * XXX: this could presumably be unsigned short.  Alternatively,
470 	 * 32-bit kernels could be taught to use fsindex instead.
471 	 */
472 	unsigned long fs;
473 	unsigned long gs;
474 #endif
475 
476 	/* Save middle states of ptrace breakpoints */
477 	struct perf_event	*ptrace_bps[HBP_NUM];
478 	/* Debug status used for traps, single steps, etc... */
479 	unsigned long           virtual_dr6;
480 	/* Keep track of the exact dr7 value set by the user */
481 	unsigned long           ptrace_dr7;
482 	/* Fault info: */
483 	unsigned long		cr2;
484 	unsigned long		trap_nr;
485 	unsigned long		error_code;
486 #ifdef CONFIG_VM86
487 	/* Virtual 86 mode info */
488 	struct vm86		*vm86;
489 #endif
490 	/* IO permissions: */
491 	struct io_bitmap	*io_bitmap;
492 
493 	/*
494 	 * IOPL. Privilege level dependent I/O permission which is
495 	 * emulated via the I/O bitmap to prevent user space from disabling
496 	 * interrupts.
497 	 */
498 	unsigned long		iopl_emul;
499 
500 	unsigned int		iopl_warn:1;
501 
502 	/*
503 	 * Protection Keys Register for Userspace.  Loaded immediately on
504 	 * context switch. Store it in thread_struct to avoid a lookup in
505 	 * the tasks's FPU xstate buffer. This value is only valid when a
506 	 * task is scheduled out. For 'current' the authoritative source of
507 	 * PKRU is the hardware itself.
508 	 */
509 	u32			pkru;
510 
511 #ifdef CONFIG_X86_USER_SHADOW_STACK
512 	unsigned long		features;
513 	unsigned long		features_locked;
514 
515 	struct thread_shstk	shstk;
516 #endif
517 
518 	/* Floating point and extended processor state */
519 	struct fpu		fpu;
520 	/*
521 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
522 	 * the end.
523 	 */
524 };
525 
526 extern void fpu_thread_struct_whitelist(unsigned long *offset, unsigned long *size);
527 
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)528 static inline void arch_thread_struct_whitelist(unsigned long *offset,
529 						unsigned long *size)
530 {
531 	fpu_thread_struct_whitelist(offset, size);
532 }
533 
534 static inline void
native_load_sp0(unsigned long sp0)535 native_load_sp0(unsigned long sp0)
536 {
537 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
538 }
539 
native_swapgs(void)540 static __always_inline void native_swapgs(void)
541 {
542 #ifdef CONFIG_X86_64
543 	asm volatile("swapgs" ::: "memory");
544 #endif
545 }
546 
current_top_of_stack(void)547 static __always_inline unsigned long current_top_of_stack(void)
548 {
549 	/*
550 	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
551 	 *  and around vm86 mode and sp0 on x86_64 is special because of the
552 	 *  entry trampoline.
553 	 */
554 	if (IS_ENABLED(CONFIG_USE_X86_SEG_SUPPORT))
555 		return this_cpu_read_const(const_cpu_current_top_of_stack);
556 
557 	return this_cpu_read_stable(cpu_current_top_of_stack);
558 }
559 
on_thread_stack(void)560 static __always_inline bool on_thread_stack(void)
561 {
562 	return (unsigned long)(current_top_of_stack() -
563 			       current_stack_pointer) < THREAD_SIZE;
564 }
565 
566 #ifdef CONFIG_PARAVIRT_XXL
567 #include <asm/paravirt.h>
568 #else
569 
load_sp0(unsigned long sp0)570 static inline void load_sp0(unsigned long sp0)
571 {
572 	native_load_sp0(sp0);
573 }
574 
575 #endif /* CONFIG_PARAVIRT_XXL */
576 
577 unsigned long __get_wchan(struct task_struct *p);
578 
579 extern void select_idle_routine(void);
580 extern void amd_e400_c1e_apic_setup(void);
581 
582 extern unsigned long		boot_option_idle_override;
583 
584 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
585 			 IDLE_POLL};
586 
587 extern void enable_sep_cpu(void);
588 
589 
590 /* Defined in head.S */
591 extern struct desc_ptr		early_gdt_descr;
592 
593 extern void switch_gdt_and_percpu_base(int);
594 extern void load_direct_gdt(int);
595 extern void load_fixmap_gdt(int);
596 extern void cpu_init(void);
597 extern void cpu_init_exception_handling(bool boot_cpu);
598 extern void cpu_init_replace_early_idt(void);
599 extern void cr4_init(void);
600 
601 extern void set_task_blockstep(struct task_struct *task, bool on);
602 
603 /* Boot loader type from the setup header: */
604 extern int			bootloader_type;
605 extern int			bootloader_version;
606 
607 extern char			ignore_fpu_irq;
608 
609 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
610 #define ARCH_HAS_PREFETCHW
611 
612 #ifdef CONFIG_X86_32
613 # define BASE_PREFETCH		""
614 # define ARCH_HAS_PREFETCH
615 #else
616 # define BASE_PREFETCH		"prefetcht0 %1"
617 #endif
618 
619 /*
620  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
621  *
622  * It's not worth to care about 3dnow prefetches for the K6
623  * because they are microcoded there and very slow.
624  */
prefetch(const void * x)625 static inline void prefetch(const void *x)
626 {
627 	alternative_input(BASE_PREFETCH, "prefetchnta %1",
628 			  X86_FEATURE_XMM,
629 			  "m" (*(const char *)x));
630 }
631 
632 /*
633  * 3dnow prefetch to get an exclusive cache line.
634  * Useful for spinlocks to avoid one state transition in the
635  * cache coherency protocol:
636  */
prefetchw(const void * x)637 static __always_inline void prefetchw(const void *x)
638 {
639 	alternative_input(BASE_PREFETCH, "prefetchw %1",
640 			  X86_FEATURE_3DNOWPREFETCH,
641 			  "m" (*(const char *)x));
642 }
643 
644 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
645 			   TOP_OF_KERNEL_STACK_PADDING)
646 
647 #define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
648 
649 #define task_pt_regs(task) \
650 ({									\
651 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
652 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
653 	((struct pt_regs *)__ptr) - 1;					\
654 })
655 
656 #ifdef CONFIG_X86_32
657 #define INIT_THREAD  {							  \
658 	.sp0			= TOP_OF_INIT_STACK,			  \
659 	.sysenter_cs		= __KERNEL_CS,				  \
660 }
661 
662 #else
663 extern unsigned long __top_init_kernel_stack[];
664 
665 #define INIT_THREAD {							\
666 	.sp	= (unsigned long)&__top_init_kernel_stack,		\
667 }
668 
669 #endif /* CONFIG_X86_64 */
670 
671 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
672 					       unsigned long new_sp);
673 
674 /*
675  * This decides where the kernel will search for a free chunk of vm
676  * space during mmap's.
677  */
678 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
679 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
680 
681 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
682 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
683 
684 /* Get/set a process' ability to use the timestamp counter instruction */
685 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
686 #define SET_TSC_CTL(val)	set_tsc_mode((val))
687 
688 extern int get_tsc_mode(unsigned long adr);
689 extern int set_tsc_mode(unsigned int val);
690 
691 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
692 
per_cpu_llc_id(unsigned int cpu)693 static inline u32 per_cpu_llc_id(unsigned int cpu)
694 {
695 	return per_cpu(cpu_info.topo.llc_id, cpu);
696 }
697 
per_cpu_l2c_id(unsigned int cpu)698 static inline u32 per_cpu_l2c_id(unsigned int cpu)
699 {
700 	return per_cpu(cpu_info.topo.l2c_id, cpu);
701 }
702 
703 #ifdef CONFIG_CPU_SUP_AMD
704 /*
705  * Issue a DIV 0/1 insn to clear any division data from previous DIV
706  * operations.
707  */
amd_clear_divider(void)708 static __always_inline void amd_clear_divider(void)
709 {
710 	asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
711 		     :: "a" (0), "d" (0), "r" (1));
712 }
713 
714 extern void amd_check_microcode(void);
715 #else
amd_clear_divider(void)716 static inline void amd_clear_divider(void)		{ }
amd_check_microcode(void)717 static inline void amd_check_microcode(void)		{ }
718 #endif
719 
720 extern unsigned long arch_align_stack(unsigned long sp);
721 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
722 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
723 
724 void default_idle(void);
725 #ifdef	CONFIG_XEN
726 bool xen_set_default_idle(void);
727 #else
728 #define xen_set_default_idle 0
729 #endif
730 
731 void __noreturn stop_this_cpu(void *dummy);
732 void microcode_check(struct cpuinfo_x86 *prev_info);
733 void store_cpu_caps(struct cpuinfo_x86 *info);
734 
735 enum l1tf_mitigations {
736 	L1TF_MITIGATION_OFF,
737 	L1TF_MITIGATION_FLUSH_NOWARN,
738 	L1TF_MITIGATION_FLUSH,
739 	L1TF_MITIGATION_FLUSH_NOSMT,
740 	L1TF_MITIGATION_FULL,
741 	L1TF_MITIGATION_FULL_FORCE
742 };
743 
744 extern enum l1tf_mitigations l1tf_mitigation;
745 
746 enum mds_mitigations {
747 	MDS_MITIGATION_OFF,
748 	MDS_MITIGATION_AUTO,
749 	MDS_MITIGATION_FULL,
750 	MDS_MITIGATION_VMWERV,
751 };
752 
753 extern bool gds_ucode_mitigated(void);
754 
755 /*
756  * Make previous memory operations globally visible before
757  * a WRMSR.
758  *
759  * MFENCE makes writes visible, but only affects load/store
760  * instructions.  WRMSR is unfortunately not a load/store
761  * instruction and is unaffected by MFENCE.  The LFENCE ensures
762  * that the WRMSR is not reordered.
763  *
764  * Most WRMSRs are full serializing instructions themselves and
765  * do not require this barrier.  This is only required for the
766  * IA32_TSC_DEADLINE and X2APIC MSRs.
767  */
weak_wrmsr_fence(void)768 static inline void weak_wrmsr_fence(void)
769 {
770 	alternative("mfence; lfence", "", ALT_NOT(X86_FEATURE_APIC_MSRS_FENCE));
771 }
772 
773 #endif /* _ASM_X86_PROCESSOR_H */
774